HTO Guide With Optional Guided ACL/PCL Tunnels

ABSTRACT

A patient-specific osteotomy guide according to the present disclosure includes a three-dimensional bone-engaging inner surface configured to closely mate and conform to a corresponding portion of a specific patient&#39;s tibia. A resection slot at a patient-specific position and orientation to guide a cutting tool to perform an osteotomy according to a preoperative plan for the patient. An axial guide at a patient-specific position and orientation to guide a tool to perform an ACL/PCL reconstructive procedure according to a preoperative plan for the patient.

FIELD

The present disclosure relates to instrumentation for use in a high tibial osteotomy (HTO) and, more specifically, to an HTO guide that additionally is used in a joint osteotomy and an anterior cruciate ligament (ACL) reconstruction and/or posterior cruciate ligament (PCL) reconstruction.

BACKGROUND

This section provides background information related to the present disclosure which is not necessarily prior art.

Osteotomies of the knee are an important technique for treating knee osteoarthritis and abnormal knee geometries. Most knee osteotomies are designed to modify the geometry of the tibia, so as to adjust the manner in which the load is transferred across the knee joint.

There are essentially two ways in which to adjust the orientation of the tibia: a closed wedge osteotomy; and an open wedge osteotomy. When performing the closed wedge osteotomy, a wedge of bone is removed from the upper portion of the tibia, and then the tibia is manipulated so as to close the resulting gap. This reorients the lower portion of the tibia relative to the tibial plateau and adjusts the manner in which load is transferred from the femur to the tibia. When performing the open wedge osteotomy, a cut is made into the upper portion of the tibia, the tibia is manipulated so as to open a wedge-like opening in the bone, and then the bone is secured in this position (e.g., by screwing metal plates to the bone or by inserting a wedge-shaped implant into the opening in the bone). This reorients the lower portion of the tibia relative to the tibial plateau and adjusts the manner in which load is transferred from the femur to the tibia.

Approximately 50% of high tibial osteotomy cases include an ACL and/or PCL repair procedure. During an ACL reconstruction procedure and/or PCL reconstruction procedure, an ACL tunnel and/or PCL tunnel is drilled through the tibia and femur. A new ligament is attached to the bone in place of the torn ACL ligament and/or PCL ligament. Thus, the surgeon must plan the trajectory of the ACL tunnel and/or PCL tunnel while performing the osteotomy and use separate standard ACL and/or PCL guides and instruments after the HTO procedure is performed.

SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

A patient-specific osteotomy guide according to the present disclosure includes a three-dimensional bone-engaging inner surface configured to closely mate and conform to a corresponding portion of a specific patient's tibia. A resection slot at a patient-specific position and orientation to guide a cutting tool to perform an osteotomy according to a preoperative plan for the patient. An axial guide at a patient-specific position and orientation to guide a tool to perform an ACL/PCL reconstructive procedure according to a preoperative plan for the patient.

A patient-specific osteotomy system according to the present disclosure includes an osteotomy cutting tool and at least one of an ACL tunnel forming tool and a PCL tunnel forming tool. The patient-specific osteotomy system further includes a single integrated osteotomy guide having a three-dimensional bone-engaging inner surface configured to closely mate and conform to a corresponding portion of a specific patient's tibia. A resection slot at a patient-specific position and orientation to guide the osteotomy cutting tool to perform an osteotomy according to a preoperative plan for the patient. An axial guide is at a patient-specific position and orientation to guide the at least one of the ACL tunnel forming tool and the PCL tunnel forming tool to perform at least one of an ACL reconstructive procedure and a PCL reconstructive procedure according to the preoperative plan for the patient.

A method of performing a patient-specific osteotomy according to the present disclosure includes aligning a three dimensional inner surface of a patient-specific guide configured to closely mate and conform to a corresponding portion of a patient's tibia in only one position and orientation; forming a patient-specific ligament tunnel in the patient's tibia using the patient-specific guide; cutting a slot into the patient's tibia along an osteotomy guide slot of the patient-specific guide a predetermined distance into the tibia; and inserting a ligament replacement into an aperture created by forming the ligament tunnel in the patient's tibia.

In another embodiment, an osteotomy method according to the present disclosure includes attaching a patient-specific osteotomy guide to a corresponding surface of a tibia of a patient, the osteotomy guide configured during a preoperative pan for the patient to mate only in one position on the corresponding surface of the tibia; drilling a guiding hole into the tibia through a drill hole of the osteotomy guide; making an osteotomy at a patient-specific orientation through a resection slot of the osteotomy guide and configured for the specific patient during the preoperative plan of the patient; drilling an ACL/PCL tunnel at a patient-specific orientation through a cylindrical aperture of the osteotomy guide, the cylindrical aperture configured for the specific patient during the preoperative plan of the patient; removing the osteotomy guide; positioning the tibia relative to the osteotomy; and securing the tibia relative to the osteotomy.

A method of forming an osteotomy guide includes determining a lateral plateau point on a plane across a plateau of a tibia of a patient; determining a tibia hinge axis from an intersection of a plane through a point a first predetermined distance below the lateral plateau point and a plane through a point a second predetermined distance medial to the lateral plateau point; determining a tibia saw entry point on a plane through the tibia hinge axis; determining a correction angle; determining a tunnel entry point and angle with respect to a longitudinal axis through the center of the tibia; and generating an osteotomy guide reflecting the tibia saw entry point, an angle of the plane through the hinge axis, the tunnel entry point, and the tunnel angle.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of an alignment guide on a patient's tibia according to the present disclosure;

FIG. 2 is a posterior perspective view of the alignment guide of FIG. 1 on the medial side of the patient's tibia;

FIG. 3 is an anterior perspective view of the alignment guide of FIG. 1 on the medial side of the patient's tibia;

FIG. 4 is a superior view of the alignment guide on the patient's tibia of FIG. 1;

FIG. 5 is another posterior perspective view of the alignment guide of FIG. 1 during an open-wedge osteotomy;

FIG. 6 is another posterior perspective view of the alignment guide of FIG. 1 during an open-wedge osteotomy;

FIG. 7 is another posterior perspective view of the alignment guide of FIG. 1 during an open-wedge osteotomy;

FIG. 8 is an anterior view of a patient's tibia during the open-wedge osteotomy;

FIG. 9 is another anterior view of the patient's tibia during the open-wedge osteotomy;

FIG. 10 is another anterior view of the patient's tibia during the open-wedge osteotomy;

FIG. 11 is another anterior view of the patient's tibia during the open-wedge osteotomy;

FIG. 12 is a posterior view of an alignment guide on a medial portion of a tibia during a closed-wedge osteotomy;

FIG. 13 is another posterior view of the alignment guide of FIG. 12 during the closed-wedge osteotomy;

FIG. 14 is another posterior view of the patient's tibia during the closed-wedge osteotomy;

FIG. 15 is another posterior view of the patient's tibia during the closed-wedge osteotomy;

FIG. 16 is a flow diagram illustrating a method of forming the alignment guide of FIGS. 1 and 12; and

FIG. 17 is a flow diagram illustrating a method of using the alignment guide of FIGS. 1 and 12.

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference to the accompanying drawings.

The present teachings generally provide for a patient specific alignment guide for use in osteotomy, such as high tibia osteotomy (HTO), for example. The patient-specific alignment guide can be used either with conventional or patient-specific implant components prepared with computer-assisted image methods. Computer modeling may be used to obtain three dimensional images of the patient's anatomy using MRI or CT scans of the patient's anatomy and the patient specific prosthesis components, and the patient-specific guides and templates can be provided by various CAD programs and/or software available.

The patient-specific alignment guides and associated patient-specific implants disclosed herein can be generally formed using computer modeling based on the patient's 3-D anatomic image generated from image scans. The patient-specific alignment guides can have a three-dimensional engagement surface that is made to conformingly contact and match a three-dimensional image of the patient's bone surface (selectively with or without soft tissue), by the computer methods discussed above. The patient-specific alignment guides can include custom-made guiding formations, such as, for example, guiding bores or cannulated guiding posts or cannulated guiding extensions or receptacles that can be used for supporting or guiding other instruments, such as drill guides, reamers, cutters, cutting guides and cutting blocks or for inserting pins or other fasteners according to a surgeon-approved pre-operative plan.

In various embodiments, the patient-specific alignment guide can include one or more patient-specific cutting guides for receiving and guiding a cutting blade at corresponding patient-specific cutting plane orientations relative to a selected anatomic axis for the specific patient. The patient-specific alignment guides can also include one or more patient-specific drilling guides for receiving and guiding a drill at corresponding patient-specific drilling axis orientations relative to the selected anatomic axis for the specific patient. The patient-specific alignment guides can also include guiding formations for guiding the implantation of patient-specific or off-the-shelf implants associated with the osteotomy procedure, such as implantable wedges and implantable fixation plates. The geometry, shape and orientation of the various features of the patient-specific alignment guide, as well as various patient-specific implants and other patient-specific tools can be determined during the pre-operative planning stage of the procedure in connection with the computer-assisted modeling of the patient's anatomy. During the pre-operative planning stage, patient-specific alignment guides, implants and other tools, can be designed and manufactured for a specific patient with input from a surgeon or other professional associated with the surgical procedure, as described in the commonly assigned and co-pending patent applications listed in the cross reference section and incorporated herein by reference.

In the following discussion, the terms “patient-specific”, “custom-made” or “customized” are defined to apply to components, including tools, implants, portions or combinations thereof, which include certain geometric features, including surfaces, curves, or other lines, and which are made to closely conform as mirror-images or negatives of corresponding geometric features of a patient's anatomy during a pre-operative planning stage based on 3-D computer images of the corresponding anatomy reconstructed from image scans of the patient by computer imaging methods. Further, patient-specific guiding features, such as, guiding apertures and guiding slots, or other holes or openings that are included in alignment guides or in implants are defined as features that are made to have positions, orientations, dimensions, shapes and and/or define cutting planes specific to the particular patient's anatomy based on the computer-assisted pre-operative plan associated with the patient.

In practice, doctors and surgeons often use osteotomy guides to assist in osteotomy procedures similar to the guides described in U.S. Pat. No. 8,632,547, incorporated herein in its entirety. Further, doctors and surgeons often use ACL and PCL guides in ACL and/or PCL procedures, such as the guide described in U.S. Pat. Nos. 6,019,767 and 5,300,077 and Deakon, Timothy, M.D., Posterior Cruciate Ligament Reconstruction Technique Using the Modular ACL/PCL Guide: Rationale and Surgical Technique, Arthrotek, A Biomet Company (2003), incorporated herein in its entirety. However, an all-in-one, integrated, modular joint osteotomy and ACL and/or PCL guide does not currently exist for when an osteotomy also calls for an ACL and/or PCL procedure. Doctors currently must perform the osteotomy procedure using the separate osteotomy guide and then perform the ACL and/or PCL procedure with other separate guides. This method adds to uncertainty in the ACL and/or PCL procedure and forces the doctor or surgeon to plan as they go during the surgery. A combined guide would allow the doctor or surgeon to trust their pre-operative planning and would contribute to greater accuracy in procedures. Further, preplanning software to determine the critical points and angles on the osteotomy guide would further contribute to greater accuracy in procedures.

Referring to FIGS. 1-4, an osteotomy alignment guide 10 for facilitating an osteotomy procedure and an ACL and/or PCL reconstruction procedure on a patient's tibia 14 and femur 18 may include an osteotomy guide 22, an ACL reconstruction guide 26 and/or a PCL reconstruction guide 30, and a three-dimensional engagement surface 34. In some embodiments, such as for an open-wedge osteotomy, osteotomy guide 22 may be in the form of a planar slot 38. In the illustrated embodiment, osteotomy guide 10 includes planar slot 38; however, osteotomy guide 10 could also include a wedge guide with two additional slots (discussed below) such that osteotomy guide may be used in both open-wedge osteotomy and closed-wedge osteotomy. In an exemplary embodiment, the osteotomy alignment guide 10 may be a patient specific osteotomy guide having the features of the alignment guide 10 determined during the pre-operative planning stage on a patient-specific (patient-customized) basis, as disclosed in U.S. Pat. No. 8,632,547, which is incorporated herein in its entirety. The bone engaging surface 34, the slot 38 orientation, and the orientation of the ACL guide 26 and/or PCL guide 30 may each be determined during the preoperative planning stage and may be unique for each patient. However, in other embodiments, the location and orientation of the features of alignment guide 10 may be non-patient-specific and simply be an adjustable alignment guide 10 that can perform both the HTO and the ACL and/or PCL procedures without having to remove the guide 10.

With additional reference to FIGS. 5-11, planar slot guiding receptacle 38 may be oriented to define a patient-specific angle β relative to an anatomic axis A for guiding a blade 46 to form a planar cut 50. The patient-specific angle β can be determined by the surgeon during the preoperative planning stage as disclosed in U.S. Pat. No. 8,632,547, incorporated herein. The first reference axis A can be a selected anatomic axis, such as, for example a mechanical axis of the joint or leg, a mechanical axis of the femoral bone, or a mechanical axis of the tibial bone, when different from the mechanical axis of the leg. Other anatomic axes, such as axes having significantly different orientations than the orientation of axis A illustrated in FIG. 1, can be used as reference axes, including, for example, an epicondylar axis (not illustrated). The blade 46 can include depth-control indicia 48, such as ruler hatch marks on the blade 46 or a mechanical stop (not illustrated) at the predetermined depth.

As illustrated in FIGS. 6 and 11, alignment guide 10 can also define one or more fixation apertures 86 for receiving fasteners to attach the alignment guide 10 to the tibia 14 (FIG. 6). Guiding receptacles, such as guiding apertures 94, may be in the same location as fixation apertures 86 and may be provided for preparing fastener holes in tibia 14. In other embodiments, guiding receptacles 94 may be different from fixation apertures 86 (not illustrated). The fastener holes formed in tibia 14 may be used in attaching a fixation plate 102 and may receive bone fixation fasteners 90 through a plurality of apertures 98 of fixation plate 102 for securing fixation plate 102 to tibia 14 (FIG. 11). In an exemplary embodiment, the location and orientation of planar slot 38, apertures 86 for fasteners 90, and guiding apertures 94 relative to alignment guide 10 can be determined during the pre-operative planning stage on a patient-specific (patient customized) basis.

Guide 10 also includes the integrated ACL alignment guide 26 and/or PCL alignment guide 30. ACL alignment guide 26 and PCL alignment guide 30 may be cylindrical alignment guides defining an aperture 106 extending through the ACL alignment guide 26 and PCL alignment guide 30. During preoperative planning, it will be determined if an ACL reconstruction procedure and/or a PCL reconstruction procedure is required. Once determined, the corresponding guide will be integrated into guide 10. While, in general, most procedures only utilize one of the ACL guide 26 and the PCL guide 30, the alignment guide 10 is capable of implementing both the ACL guide 26 and PCL guide 30 if necessary.

It is noted that while the illustrations and specification may generally refer only to the ACL alignment guide 26 and/or the ACL reconstruction procedure, it is understood that the description also applies to the PCL alignment guide 30 and/or the PCL reconstruction procedure. Alignment guide 10 may be equipped with one or both of the ACL alignment guide 26 and the PCL alignment guide 30, and one or both of the ACL reconstructive procedure and the PCL reconstructive procedure may be performed during the open-wedge or close-wedge osteotomy procedure.

ACL alignment guide 26 may be oriented to define patient-specific angle φ₁ relative to anatomic axis A for guiding a drill or drill bit 110 to form an ACL tunnel 114. PCL alignment guide 30 may be oriented to define patient-specific angle φ₂ relative to anatomic axis A for guiding drill or drill bit 110 to form a PCL tunnel 118. The drill 110 can include depth-control indicia, such as hatch marks on the drill bit (not illustrated), a mechanical stop on the drill (not illustrated), or any other known depth-control mechanisms. In an exemplary embodiment, the location and orientation of ACL and/or PCL alignment guide 26, 30 and angles φ₁ and φ₂ relative to alignment guide 10 can be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis and taking into account the correction of the HTO procedure as disclosed in U.S. Pat. No. 8,632,547, incorporated herein. However, in other embodiments, the location and orientation of ACL and/or PCL alignment guide 26, 30 relative to alignment guide 10 may be non-patient-specific with adjustable alignment guide 10 that can perform both the HTO and the ACL and/or PCL procedures without having to remove the guide 10.

In an example embodiment, three-dimensional (3-D) engagement surface 34 may be a 3-D patient-specific engagement surface and may be made to conform to a corresponding outer surface of patient's tibia 14 during the pre-operative planning stage. 3-D engagement surface 34 may be made to conform to the corresponding outer surface of the patient's tibia 14 by a computer-assisted method utilizing a 3-D image of the patient's tibia, as discussed previously. In the example embodiment, 3-D engagement surface 34 may only mate with the patient's tibia 14 at one location and in one position. The 3-D engagement surface 34 may be a negative of the outer surface of the patient's tibia 14 such that the surface of the tibia 14 and the engagement surface 34 are mirror images. The 3-D engagement surface 34 can be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein. However, in other embodiments, 3-D engagement surface may be a planar surface and may be retained on the tibia by screws, adhesive, or any other known fixation mechanism.

Now referring specifically to FIGS. 6-11, an illustration of an exemplary open-wedge high tibial osteotomy procedure in a knee joint 126 between tibia 14 and femur 18 is illustrated. In this example, during preoperative planning, a determination that an ACL procedure is needed and the ACL alignment guide is determined after taking into account the position and angle of the osteotomy guide 22 and using procedures disclosed in U.S. Pat. No. 8,632,547, incorporated herein. During surgery, alignment guide 10 is placed on a medial side of a patient's tibia 14, such that 3-D engagement surface 34 of alignment guide 10 closely conforms to the corresponding portion of the tibia 14. The alignment guide 10 may be shifted until it nests in only one location on the tibia 14, as designed during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein. Alignment guide 10 is fixed to the tibia 14 by any known method. For example, as illustrated in FIG. 6, fixation apertures 86 may be utilized for preparing fastener holes in tibia 14. Fixation apertures 86 may receive bone fixation fasteners (not illustrated), fixing alignment guide 10 to the tibia 14. In other embodiments, alignment guide 10 may be fixed to tibia 14 with adhesive, K-wires, or any other known fastener.

Referring specifically to FIG. 6, ACL tunnel 114 at angle φ relative to anatomic axis A of knee joint 126 can be formed using alignment guide 10 of the present teachings. The axis defined by ACL guide 26 is shown in phantom at corresponding angle φ relative to reference/anatomic axis A, as discussed above in connection with FIG. 6. In an exemplary embodiment, ACL tunnel 114 may be formed by drilling.

ACL tunnel 114 may be drilled through at least tibia 14 and also may be drilled into or through femur 18 while the knee is in flexsion. Angle φ of ACL tunnel 114 relative to axis A can be determined during the pre-operative planning stage of the osteotomy and in relation to corresponding alignment guide 10. In an example embodiment, angle φ of ACL tunnel 114 may be determined such that ACL tunnel 114 does not intersect with partial planar cut 50. However, in an alternative embodiment, angle φ of ACL tunnel 114 may be determined such that ACL tunnel 114 intersects with partial planar cut 50.

Referring specifically to FIG. 7, once ACL tunnel 114 is formed, planar cut 50 at selected angle β relative to first reference axis A of knee joint 126 may be made. Blade 46 can be used for the plane cut through planar slot 38 along a plane defined by planar slot 38 at a corresponding angle β relative to reference/anatomic axis A.

As illustrated in FIGS. 8-9, planar cut 50 is a partial cut, or resection, i.e., not a through cut, and can extend from a first boundary 130 at the intersection of the planar cut 50 with outer surface of tibia 14 to a second boundary 134 at the selected patient-specific cutting depth illustrated as distance L in FIG. 8. First boundary 130 can be generally a curved line reflecting the curvature of outer surface of tibia 14. Second boundary 134 can be substantially a straight line as formed by the saw blade. Second boundary 134 can function as a hinge line (also referenced with numeral 134) for opening a wedge or osteotomy angle γ between first and second opposing faces 138, 142 of cut 50, as illustrated by arrows C in FIG. 9. Osteotomy angle γ and first and second boundaries 130, 134 are patient-specific and can be selected during the pre-operative planning stage.

With reference to FIGS. 10-11, a patient-specific implantable wedge 170 having corresponding wedge angle γ defined between first and second planar surfaces 174, 178 is shown. Wedge 170 can be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein. Wedge 170 can be inserted and/or pushed between first and second faces 138, 142 of cut 50. Wedge 170 is inserted while cut 50 is partially open, i.e., while first and second faces 138, 142 form an angle smaller than the angle γ, for guiding and facilitating the correct wedge opening to form pre-selected angle γ. It will be appreciated, however, that cut 50 can be opened to an angle γ, using any other tool, such as trial wedge having the same angle γ. In some embodiments, cut 50 may be opened at an angle greater than γ.

First and second planar surfaces 174, 178 of implantable wedge 170 can meet at a straight edge or truncated plane surface 182. Upon insertion of implantable wedge 170, cut 50 is opened and secured to selected angle γ by implantable wedge 170. First and second planar surfaces 174, 178 of implantable wedge 170 can abut against first and second faces 138, 142 of planar cut 50, and edge 182 of implantable wedge 170 can abut second boundary 134 of planar cut 50. Implantable wedge 170 can have a patient-specific boundary surface 186 opposite to the edge/surface 182. The boundary surface 186 is designed during the pre-operative planning stage as a continuous surface that mates to the outer bone contour and provides a continuous contour relative to the contour of tibia 14 on either side of cut 50. Implantable wedge 170 can also be secured directly in the bone with sutures, pins, anchors or other fasteners. In some embodiments, implantable wedge 170 can be cemented or coated with materials promoting bone in-growth. If, during the preoperative planning, implantable fixation plate 102 is determined to be necessary, the fixation plate 102 will be affixed to the patient-specific boundary surface 186 after the ACL procedure is complete as described in further detail below.

With continued reference to FIGS. 8-11, ACL tunnel 114 defines an aperture in tibia 14 and femur 18 for receiving an ACL replacement implant 146. The ACL replacement implant 146 may be any known ligament replacement such as a bone-tendon-bone implant of the type described in U.S. Pat. No. 5,282,802, which is incorporated herein in its entirety. Other examples of types of replacement implants 146 that may be used are a semi-tendonosis/gracilis graft, a hamstring graft, or any other graft known. It is envisioned the physician may determine the desired graft or graft assembly length and appropriate graft tension during the pre-operative planning stage of the osteotomy and in conjunction with alignment guide 10.

In an exemplary embodiment having a blind-bore, a first portion 150 of the ligament replacement 146 is coupled within a femoral tunnel 154 using a fastener, for example an interference screw, positioned within the tunnel 114. In another embodiment, such as for a semi-tendonosis/gracilis graft, with the femur having a through-bore, the first portion 150 of the ligament replacement 146 may be pulled through the femoral tunnel 154 and exit the femur 18. An anchor (not illustrated) may retain the first portion 150 on the exterior of the femur 18.

A second portion 158 of ligament replacement 146 is pulled taught into a tibial tunnel 162 and coupled to tibia 14 using a second fastener 166. For example only, the second fastener 166 may be a transverse or parallel bone engaging screw 166. While second portion 158 is described and illustrated as being coupled using second fastener 166, it is understood that any method of fastening or retaining second portion 158 within tibial tunnel 162 may be used. In some embodiments, wedge 170 may include a portion of tibial tunnel 162, and second portion 158 may be fastened within wedge 170.

In embodiments related to FIGS. 1-11, the ACL tunnel 114 may intersect with planar cut 50 and/or wedge implant 170. During this procedure, a surgeon will nest alignment guide 10 on tibia 14. ACL tunnel 114 is then drilled in tibia 14 and femur 18. Planar cut 50 is made with blade 46, and, if applicable, wedge 170 is inserted. Wedge 170 may include a tunnel 172 that aligns with the ACL tunnel 114. The surgeon then performs the ACL repair or inserts ACL implant 146 as previously discussed.

After performing the ACL replacement procedure, referring to FIG. 11, if implantable fixation plate, or modular attachment plate, 102 was determined to be necessary during preoperative planning, the implantable fixation plate 102 can be used in combination with implantable wedge 170. Patient-specific implantable wedge 170 and fixation plate 102 can be modularly connected, as illustrated in FIG. 11, or can be provided as a single monolithic and integrally formed component. A modular connection can include a dovetail connection illustrated at reference numerals 194 and 198 corresponding to opposing connection formations of fixation plate 102 and implantable wedge 170. Other connection formations can include a taper lock connection, various groove and tongue connections, or connections with threadable fasteners or other biocompatible fasteners. The modular connection can be formed at a common boundary 202 between fixation plate 102 and implantable wedge 170.

Fixation plate 102 can include patient-specific surfaces 206 a, 206 b on either side of implantable wedge 170 and can be anchored to tibia 14 using bone pins or other bone fasteners 98 that pass through corresponding apertures 90 in tibia 14 and fixation plate 102. The location and orientation of apertures 90 can also be patient-specific and determined during the pre-operative planning stage for the particular patient.

Now referring to FIGS. 12-15, an exemplary closed-wedge high tibial osteotomy guide 300 and procedure is illustrated in association with knee joint 126 between tibia 14 and femur 18. Referring specifically to FIGS. 12-13, alignment guide 300 may be substantially similar to alignment guide 10 and may include many of the same features as alignment guide 10. It is understood that alignment guide 300 includes the same features as alignment guide 10 unless called out in the description below.

Alignment guide 300 may include a wedge guide 304 for forming a plurality of planar cuts 50 a, 50 b of a removable bone wedge 308 during a close-wedge osteotomy. Wedge guide 304 may include first and second surfaces 316, 320 and first and second slots 324, 328 for guiding blade 46 to form planar cuts 50 a, 50 b. Planar cuts 50 a, 50 b are oriented at selected first and second angles β₁ and β₂ relative to reference/anatomic axis A. First and second angles β₁ and β₂ of planar cuts 50 a, 50 b relative to reference axis A can be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein.

Referring additionally to FIGS. 14-15, an illustration of an exemplary close-wedge high tibial osteotomy procedure in a knee joint 126 between tibia 14 and femur 18 is illustrated. Alignment guide 300 is placed on a medial side of proximal tibia 14, such that three-dimensional engagement surface 34 of alignment guide 300 closely conforms to the corresponding portion of tibia 14. Alignment guide 300 nests in only one position on tibia 14. Alignment guide 300 is fixed to tibia 14 as previously discussed.

After nesting the alignment guide 300 on the tibia 14, ACL tunnel 114 at angle φ₁ relative to anatomic axis A of knee joint 126 may be formed, for example, by using drill 110 and alignment guide 300 of the present teachings. The axis defined by ACL guide 26 is shown in phantom at a corresponding angle φ₁ relative to reference/anatomic axis A, as previously discussed. Drill 110 can be used for drilling ACL tunnel 114 through ACL guide 26. ACL tunnel 114 may be drilled through at least tibia 14 and also may be drilled through femur 18, as previously discussed in relation to the open-wedge osteotomy procedure.

Referring specifically to FIG. 13, once ACL tunnel 114 is formed, first and second partial planar cuts 50 a, 50 b may be made using blade 46 and alignment guide 10 of the present teachings. The plane defined by the first and second slots 324, 328 is shown in phantom at corresponding first and second angles β₁ and β₂ relative to reference/anatomic axis A. Planar cuts 50 a and 50 b can be formed by using, for example, blade 46 to cut through first and second slots 324, 328. First and second planar cuts 50 a, 50 b can intersect at a hinge line 332.

In the example embodiment, first and second angles β₁ and β₂ of planar cuts 50 a, 50 b define bone wedge 308 of predetermined wedge angle γ=β₁−β₂. Now referring to FIGS. 14-15, bone wedge 308 can be removed and the corresponding wedge opening can be closed by bringing the surfaces of first and second cuts 50 a, 50 b in contact by rotating about hinge line 332.

A first (or osteotomy-side) patient-specific fixation plate 336 can be attached to tibia 14 to secure first and second cuts 50 a, 50 b in contact after bone wedge 308 is removed. Patient-specific fixation plate 336 may include a patient-specific engagement surface 340 is made to conform to a corresponding outer surface of patient's tibia 14. In the example embodiment, patient-specific engagement surface 340 may only mate with the patient's tibia 14 at one location and in one position. The patient-specific engagement surface 340 may be a negative of the outer surface of the patient's tibia 14 such that the surface of the tibia 14 and the patient-specific engagement surface 340 are mirror images. Patient-specific engagement surface 340 may be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein. In fixation plate 336 the same reference numerals are used to indicate features having the same functions as in fixation plate 102. Fixation plate 336 can include apertures 330 at patient-specific positions and orientations for guiding bone fixation fasteners 210 through apertures 330 and into tibia 14. First and second cuts 50 a, 50 b can also be secured by pins, sutures or other fasteners to the bone.

ACL tunnel 114 defines an aperture in tibia 14 and perhaps femur 18 for receiving ACL replacement implant 146. ACL replacement implant 146 may be any known ligament replacement such as a bone-tendon-bone implant of the type described in U.S. Pat. No. 5,282,802, incorporated herein. Other examples of types of replacement implants 146 that may be used are a semi-tendonosis/gracilis graft, a hamstring graft, or any other graft known. The ACL and/or PCL procedure may then be performed as previously discussed.

In embodiments related to FIGS. 12-15, the ACL tunnel 114 may intersect with planar cuts 50 a, 50 b. During this procedure, a surgeon will nest alignment guide 10 on tibia 14. ACL tunnel 114 is then drilled in tibia 14 and femur 18. Planar cuts 50 a, 50 b are made with blade 46. The surgeon then performs the ACL repair by removing bone wedge 308 as previously discussed. As the replacement implant 146 is inserted through area of planar cuts 50 a, 50 b, the replacement implant 146 is adjusted as the faces of the planar cuts 50 a, 50 b are brought together.

Now referring to FIG. 16, a method 400 for creating the osteotomy guide 10, 300 is illustrated. In some embodiments, method 400 may be implemented during the pre-operative planning stage of the osteotomy and in conjunction with designing the alignment guide 10, 200. Further, in some embodiments, method 400 may be implemented in a software program for a computer, and in other embodiments, method 400 may be implemented by a doctor or surgeon.

Method 400 determines the segmented bones and initial planning points at block 404. For example, images of a patient's femur 18 and tibia 14 may be loaded into a computer program or may be viewed by the surgeon. During segmentation, a user places points at a femoral head center and talus and identifies a mechanical axis B connecting these points. The mechanical axis B can be seen in FIG. 8. The mechanical axis B extends from a proximal femoral head point to the talus point.

At block 408, method 400 defines a proximal tibia slice 409 (also illustrated in FIG. 8). The proximal tibia slice 409 is perpendicular to the mechanical axis and through a point above a tuberosity 410 and below osteophytes 411. A point at the center of the proximal tibia slice 409 is the proximal end of the tibia mechanical axis B. The tibia mechanical axis B extends from the proximal point 413 to the talus point 406.

At block 412, method 400 creates a best fit circle 414 to a medial tibial plateau (FIG. 4). At block 416, method 400 defines a tibia plateau plane 417. The tibia plateau plane 417 is through the best fit circle 414 center and perpendicular to the tibia mechanical axis A (FIG. 4). A tibia AP axis C connects the tuberosity point 410 and a posterior sulcus point 418. A tibia AP plane 419 is parallel to the tibia AP axis C and tibia mechanical axis B and extends through the tibia plateau center point (FIG. 8).

At block 420, method 400 defines a tibia native slope 422 (FIG. 8). The tibia native slope 422 is defined as a line from the anterior to posterior aspects of the medial tibial plateau within the tibia AP plane.

At block 424, method 400 defines a tibia hinge axis 426 (FIG. 8). The tibia hinge axis is a line at the intersection of two planes: (1) a plane parallel to the native slope 422 through a predetermined point (for example only, 15 mm) below a lateral plateau point and (2) a plane parallel to the AP plane 419 through a predetermined point (for example only, 10 mm) medial to a lateral plateau point.

A tibia saw entry point 427 (FIG. 4) is defined at block 428. The tibia saw entry point 427 lies on a boarder of the tibia where a plane intersecting both the tuberosity point 410 and the hinge axis 426 intersects the border.

At block 432, method 400 defines a tibia correction landmark 433. The landmark is a predetermined distance (for example only, 62%) from the medial side along a line from the extreme medial and lateral plateau points. The center of the femoral head 405 and the talus point 406 are connected to the tibia correction landmark 433 to create correction axes D and E (FIG. 8) at block 436.

At block 440, method 400 determines the correction angle. The correction axes D and E are projected into a coronal plane which is perpendicular to the tibia AP axis C through the correction landmark 433. The correction angle is the angle between the projected correction axes D and E (FIG. 8).

At block 444, method 400 rotates the tibia 14 around the hinge axis 426 to the correction angle. At block 448, method 400 creates a section curve from the cut plane and revolves the section curve to the correction angle to create a wedge. The wedge is trimmed to a predetermined thickness (for example only, 3 mm) at block 452. The dimensions and angle of the wedge can be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein.

At block 456, method 400 determines the drill entry point and the angle of the ACL and/or PCL tunnels (FIG. 5). The longitudinal axis through the center of the femur 18 is placed at a predetermined angle (for example only, 90 degrees) relative to a longitudinal axis through the center of the tibia 14. An angle and location of the ACL and/or PCL tunnels is determined by the surgeon. The drill entry point is the location where the ACL and/or PCL tunnels intersect the boarder of the tibia. The location and dimensions of the ACL and/or PCL tunnels can be determined during the pre-operative planning stage on a patient-specific (patient-customized) basis as disclosed in U.S. Pat. No. 8,632,547, incorporated herein.

At block 460, method 400 generates the physical osteotomy guide 10, 200. The guide 10, 200 may be created through injection molding, CNC machining, or any other method known.

Now referring to FIG. 17, a method 500 for an open- or closed-wedge osteotomy using osteotomy guide 10, 200 is illustrated. At block 504, method 500 aligns the osteotomy guide 10, 200 on the patient's tibia 14. The 3-D engagement surface 34 of osteotomy guide 10, 200 conforms to the corresponding outer surface of the patient's tibia 14. In the example embodiment, 3-D engagement surface 34 may only mate with the patient's tibia 14 at one location and in one position.

At block 508, method 500 secures the guide 10, 200 to the surface of the tibia 14. The guide 10, 200 may be retained on the tibia by pins, K-wires, fasteners, adhesive, or any other known fixation mechanism.

The ACL and/or PCL tunnels 114, 118 are formed at block 512, such as by drilling, punching, or any other known method. At block 516, method 500 performs the osteotomy cut 50, 50 a, 50 b in the tibia 14. During an open-wedge osteotomy, a single cut 50 is made through slot 38. During a closed-wedge osteotomy, a plurality of cuts 50 a, 50 b are made through slots 320, 324.

At block 520, guide 10, 200 is removed from the surface of the patient's tibia 14. At block 524, method 500 either inserts an implant wedge 170 during an open-wedge osteotomy, or begins reducing the angle γ between cuts 50 a and 50 b. At block 528, method 500 inserts ACL and/or PCL implant 146 into ACL and/or PCL tunnel 114, 118. ACL and/or PCL implant 146 may be a bone-tendon-bone implant having first and second bone portions 154, 158.

First portion 154 of the ACL and/or PCL implant is secured in the proximal end of the ACL and/or PCL tunnel 114, 118 at block 532. The first portion 154 may either be secured in the tunnel 114, 118 in a blind bore configuration or the first portion 154 may be secured on the external surface of the tibia 14 or femur 18 in a through-bore configuration.

At block 536, method 500 applies tension to the ACL and/or PCL implant 146 by tensioning the second bone portion 158. At block 540, method 500 determines whether this is an open wedge osteotomy or a closed wedge osteotomy. During the closed-wedge osteotomy procedure, the remaining angle between cuts 50 a and 50 b is reduced while maintaining tension on the ACL and/or PCL implant 146 at 544. During the open-wedge osteotomy procedure, if the ACL tunnel 114 extends through the wedge 170, the wedge 170 is inserted into the tibia 14 and the ACL implant 146 is routed through the tunnel 172 in the wedge 170 while keeping tension on the ACL implant 146 at block 548. For both open and closed wedge osteotomy procedures, the second portion of bone 158 is secured in the distal end of the ACL and/or PCL tunnel 114, 118 at 552. The second bone portion 158 may either be secured in the tunnel 114, 118 on the external surface of the tibia 14.

At block 556, method 500 secures the fixation plate 102 (if necessary) to the outer surface of the tibia 14. Fixation plate 102 can be anchored to tibia 14 using bone pins or other bone fasteners 210 that pass through corresponding apertures 214 of fixation plate 102.

The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. 

What is claimed is:
 1. A patient-specific osteotomy guide comprising: a three-dimensional bone-engaging inner surface configured to closely mate and conform to a corresponding portion of a specific patient's tibia; a resection slot at a patient-specific position and orientation to guide a cutting tool to perform an osteotomy according to a preoperative plan for the patient; and an axial guide at a patient-specific position and orientation to guide a tool to perform at least one of an ACL reconstructive procedure and a PCL reconstructive procedure according to the preoperative plan for the patient.
 2. The patient-specific osteotomy guide of claim 1, further comprising an alignment portion having an alignment surface surrounding the resection slot at a patient-specific position and orientation to guide the cutting tool to perform the osteotomy according to the preoperative plan for the patient.
 3. The patient-specific osteotomy guide of claim 1, wherein the three-dimensional inner surface, slot, and axial guide are determined pre-operatively and are formed in a single, integrated guide.
 4. The patient-specific osteotomy guide of claim 1, wherein the three dimensional inner surface is configured to mate to a corresponding portion of a patient's tibia in only one position.
 5. The patient-specific osteotomy guide of claim 1, wherein the resection slot is a single slot for guiding the cutting tool during an open wedge osteotomy procedure.
 6. The patient-specific osteotomy guide of claim 1, wherein the resection slot includes a first slot and a second slot for guiding the cutting tool during a closed wedge osteotomy procedure.
 7. A patient-specific osteotomy system comprising: an osteotomy cutting tool; at least one of an ACL tunnel forming tool and a PCL tunnel forming tool; and a single integrated osteotomy guide including: a three-dimensional bone-engaging inner surface configured to closely mate and conform to a corresponding portion of a specific patient's tibia; a resection slot at a patient-specific position and orientation to guide the osteotomy cutting tool to perform an osteotomy according to a preoperative plan for the patient; and an axial guide at a patient-specific position and orientation to guide the at least one of the ACL tunnel forming tool and the PCL tunnel forming tool to perform at least one of an ACL reconstructive procedure and a PCL reconstructive procedure according to the preoperative plan for the patient.
 8. The patient-specific osteotomy system of claim 7, further comprising a wedge implant.
 9. The patient-specific osteotomy system of claim 8, wherein the wedge implant is designed to conform to a specific patient's tibia.
 10. The patient-specific osteotomy system of claim 8, wherein the wedge implant defines a tunnel.
 11. The patient-specific osteotomy system of claim 7, further comprising a fixation plate.
 12. A method of performing a patient-specific osteotomy comprising: aligning a three-dimensional inner surface of a patient-specific guide configured to closely mate and conform to a corresponding portion of a patient's tibia in only one position and orientation; forming a patient-specific ligament tunnel in the patient's tibia using the patient-specific guide; cutting a slot into the patient's tibia along an osteotomy guide slot of the patient-specific guide a predetermined distance into the tibia; and inserting a ligament replacement into an aperture created by forming the ligament tunnel in the patient's tibia.
 13. The method of claim 12, wherein cutting the patient's tibia includes cutting a first cut and a second cut forming a wedge shape into the patient's tibia by following a first osteotomy guide slot and a second osteotomy guide slot.
 14. The method of claim 13, further comprising removing the wedge from the tibia.
 15. The method of claim 14, further comprising securing a first portion of tibia corresponding to the first cut to a second portion of tibia corresponding to the second cut.
 16. The method of claim 12, further comprising inserting a wedge implant into the slot cut in the patient's tibia.
 17. The method of claim 12, wherein aligning the three-dimensional inner surface includes aligning the patient-specific guide on the patient's tibia and keeping the patient-specific guide attached during cutting the slot and forming the patient-specific ligament tunnel without removing the patient-specific guide.
 18. An osteotomy method comprising: attaching a patient-specific osteotomy guide to a corresponding surface of a tibia of a patient, the osteotomy guide configured during a preoperative pan for the patient to mate only in one position on the corresponding surface of the tibia; forming a tunnel at a patient-specific orientation through a cylindrical aperture of the osteotomy guide, the cylindrical aperture configured for the specific patient during the preoperative plan of the patient; making an osteotomy at a patient-specific orientation through a resection slot of the osteotomy guide and configured for the specific patient during the preoperative plan of the patient; removing the osteotomy guide; positioning the tibia relative to the osteotomy; and securing the tibia relative to the osteotomy.
 19. The osteotomy method of claim 16, wherein the tunnel is formed in the tibia and in a femur of the patient.
 20. The osteotomy method of claim 17, further comprising inserting a ligament replacement into the tunnel and securing a first portion of the ligament replacement in the femur and a second portion of the ligament replacement in the tibia.
 21. The osteotomy method of claim 18, wherein positioning the tibia relative to the osteotomy is opening the resection slot to an angle determined during the preoperative plan of the patient.
 22. The osteotomy method of claim 21, wherein securing the tibia relative to the osteotomy is inserting a wedge implant into the opened resection slot.
 23. The osteotomy method of claim 18, wherein positioning the tibia relative to the osteotomy is closing the osteotomy.
 24. The osteotomy method of claim 23, wherein securing the tibia relative to the osteotomy is fastening a fixation plate to fix the osteotomy in a closed position.
 25. A method of forming an osteotomy guide, comprising: determining a lateral plateau point on a plane across a plateau of a tibia of a patient; determining a tibia hinge axis from an intersection of a plane through a point a first predetermined distance below the lateral plateau point and a plane through a point a second predetermined distance medial to the lateral plateau point; determining a tibia saw entry point on a plane through the tibia hinge axis; determining a correction angle; determining a tunnel entry point and angle with respect to a longitudinal axis through the center of the tibia; and generating an osteotomy guide reflecting the tibia saw entry point, an angle of the plane through the hinge axis, the tunnel entry point, and the tunnel angle. 